Taking risks is very scary! It may take more than one (or three!) attempts. But good things come from taking chances, taking risks, making decisions that don't have a guaranteed outcome.
What's the worst that could happen?
I took a risk. I bailed out on my career after 10 years and took a new path. I was not happy. I needed a new direction. So, I did it without knowing where I would end up or how I would get there or even, really, where I wanted to end up. I just knew I needed to leave where I was. So, I took an exploratory path. I ended up in a place that so many strive for and I tripped into it! Now I have an extremely satisfying career.
But with regard to your ruminations... yeah, yeah, yeah.... what IF? You'll never know unless you try! What if you aren't really cut out to be a bullfighter, college professor, or event planner? How else are you going to learn? Then you can say..."well, I thought it was a good idea, but it didn't turn out to be all I had fantasized about". Then you make a new plan. Hell, not having a plan and just floating into the unknown can result in some pretty awesome experiences.
Divorced - recovered and hoping to help.
"We're not broken, just bent, and we can learn to love again" ~Pink